1. Field of the Invention
The present invention relates to an animal confinement system, and, more particularly, to a wireless confinement system for an animal.
2. Description of the Related Art
Pet confinement systems often include a radio frequency transmitter having a wire loop for transmitting the radio frequency signal. The wire loop antenna roughly defines the boundary in which the animal is to be confined. The animal wears a receiving unit that is attached to its collar. If the animal gets within a predetermined distance of the wire loop antenna, the receiver unit detects the radio frequency signal transmitted from the loop antenna, whereupon a correcting stimulus such as an electrical shock is applied to the animal. A problem is that it is difficult and time consuming to lay the ground loop antenna. If a discontinuity in the wire loop antenna occurs, it is then necessary to locate and repair the discontinuity. Furthermore, once the wire loop antenna is laid into the ground, the boundaries of the animal""s confinement area are fixed, and cannot be easily modified.
It is also known to use a wireless system to track a target, e.g., an article, animal or person. One such wireless system transmits an ultrasound signal to a receiver unit carried by the animal. In response to receiving the ultrasound signal, the receiver unit transmits a radio frequency signal back to the transmitter of the ultrasound signal. Since the speed of sound is known, and radio frequency signals travel practically instantaneously at the speed of light, the transmitting unit can calculate how far away from the transmitter the receiving unit is located based upon the time interval between transmitting the ultrasound signal and receiving the radio frequency signal. If that time interval exceeds a predetermined threshold, indicating that the receiving unit is further than a threshold distance away from the transmitting unit, a second radio frequency signal is transmitted from the transmitting unit to the receiving unit. Upon receiving the second radio frequency signal, the receiving unit applies a correcting stimulus to the animal.
In another such system, the transmitter modulates transmitted electromagnetic signals to produce and transmit non-random patterns of electromagnetic energy. The receiver receives the electromagnetic signals and compares the signal level of the received electromagnetic signals from the transmitter with a predetermined level. If the signal level of the received electromagnetic signals from the transmitter is less than the predetermined level, then an electronic indication of a loss of signal is produced. In addition, the phase of the modulation of the received electromagnetic signals from the transmitter is compared with a reference phase. If the phase of the received electromagnetic signals from the transmitter is not substantially in phase with the reference phase, then the electronic indication of a loss of phase is produced. The receiver also is capable of producing a warning stimulus to the pet and a control stimulus to the pet. When there is no electronic indication of a loss of signal and there is no electronic indication of a loss of phase, then the pet is considered to be in the containment area and there is no warning stimulus and there is no control stimulus to the pet. When there is an electronic indication of a loss of signal and there is no electronic indication of a loss of phase, then there is a warning stimulus to the pet. When there is an electronic indication of a loss of signal and there is an electronic indication of a loss of phase, then there is a control stimulus to the pet.
There are many problems with a wireless containment system as described above. One problem is that if the pet proceeds through the active range of the receiver/transmitter pair, the pet will continuously receive correction so long as the pet is outside the containment area or until the receiver battery has run down. Such prolonged correction of the pet without trainer intervention is ineffective, and subjects the pet to unnecessary discomfort.
In addition, using a phase detection circuit requires a large amount of output power from the transmitting unit to achieve a usable containment radius. Transmitting such a high signal level creates a potential radiation hazard for anyone in close, constant proximity to the transmitter. In order to obtain the required power, the transmitter must be supplied AC power from a household outlet. This limits the utility of the system in many ways: 1) the system is not portable, and 2) since the system is plugged into a wall outlet, much of the usable containment area is consumed by the house itself. In addition, the system is not weather resistant. Furthermore, at the receiver end of the system, using a phase detection scheme requires continuous operation, thus consuming the receiver battery more rapidly. Since such a system uses the absence of a signal to determine position relative to the containment zone, a failure within the transmitting or receiving circuit could potentially result in the animal receiving a corrective stimulus while inside the containment zone. Finally, such a prior system provides no means for applying corrective training stimulation from a separate handheld transmitter.
Therefore, what is needed in the art is a wireless animal confinement system, which: 1) efficiently uses both transmitter and receiver power to promote long battery life and low maintenance, 2) is portable and weather resistant to allow placement of the containment field in the exact area desired by the user, 3) contains built-in-test (BIT) circuitry to monitor the health of both the transmitter and receiver to prevent stimulation in the event of a failure in either unit, 4) has the capability to use a second handheld transmitter to support an independent training function and 5) does not subject the monitored animal to unnecessary discomfort due to unproductive corrective stimulation.
The present invention provides a wireless animal confinement method and system which solves one or more the listed shortcomings of the prior methods and systems.
In one form of the present invention, a location of a containment transmitter assembly is selected, and a receiver assembly is attached to the animal. The receiver assembly is adapted to selectively provide a corrective stimulation to the animal. The method of the invention includes the steps of selecting a first distance between the containment transmitter assembly and the receiver assembly to define a first zone within which no corrective stimulation is provided to the animal by the receiver assembly; selecting a second distance between the containment transmitter assembly and the receiver assembly to define a second zone beyond the first zone within which corrective stimulation is provided to the animal by the receiver assembly; and selecting a third distance between the containment transmitter assembly and the receiver assembly to define a third zone beyond the second zone within which the animal will receive no further corrective stimulation from the receiver assembly.
In another form of the invention, a location of a self contained, portable containment transmitter assembly is selected, and a receiver assembly is attached to the animal. The receiver assembly is adapted to selectively provide a corrective stimulation to the animal. The invention selects a distance between the containment transmitter assembly and the receiver assembly to define a zone within which no corrective stimulation is provided to the animal by the receiver assembly. A second zone within which the animal will receive no further corrective stimulation from the receiver assembly is defined automatically within the system.
In both forms of the invention described above, the receiver unit is further responsive to a training transmitter to deliver corrective stimulation when activated. This response is independent from any signal received from the containment transmitter.
One advantage of the invention is that it requires much less power than other types of wireless containment system allowing for longer periods between maintenance. Another advantage is that since the system can be portable and weather resistant, the containment field can be established in a more exact and useful area.
Another advantage of this system is the capability to independently train the animal using the same collar used by the containment system. An additional advantage of the invention is that the animal ceases receiving correction stimuli once the animal exceeds a predetermined distance from the transmitter assembly or a predetermined amount of consecutive stimulations have been applied, to thereby spare the animal from unnecessary discomfort due to unproductive corrective stimulation.